diff options
| author | Steve Langasek <steve.langasek@ubuntu.com> | 2012-08-29 16:51:10 -0700 |
|---|---|---|
| committer | Steve Langasek <steve.langasek@canonical.com> | 2012-08-29 16:51:10 -0700 |
| commit | 3e5756512efd00beca8e76ea70d5924056aa4714 (patch) | |
| tree | 0ec3924871c45ea16b10e5ff536e21b7a77af7c9 /Cryptlib/Pk/CryptAuthenticode.c | |
| download | efi-boot-shim-3e5756512efd00beca8e76ea70d5924056aa4714.tar.gz efi-boot-shim-3e5756512efd00beca8e76ea70d5924056aa4714.zip | |
Import upstream version 0~20120728.3df9e294
Diffstat (limited to 'Cryptlib/Pk/CryptAuthenticode.c')
| -rw-r--r-- | Cryptlib/Pk/CryptAuthenticode.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/Cryptlib/Pk/CryptAuthenticode.c b/Cryptlib/Pk/CryptAuthenticode.c new file mode 100644 index 00000000..a4f62b22 --- /dev/null +++ b/Cryptlib/Pk/CryptAuthenticode.c @@ -0,0 +1,163 @@ +/** @file
+ Authenticode Portable Executable Signature Verification over OpenSSL.
+
+ Caution: This module requires additional review when modified.
+ This library will have external input - signature (e.g. PE/COFF Authenticode).
+ This external input must be validated carefully to avoid security issue like
+ buffer overflow, integer overflow.
+
+ AuthenticodeVerify() will get PE/COFF Authenticode and will do basic check for
+ data structure.
+
+Copyright (c) 2011 - 2012, Intel Corporation. All rights reserved.<BR>
+This program and the accompanying materials
+are licensed and made available under the terms and conditions of the BSD License
+which accompanies this distribution. The full text of the license may be found at
+http://opensource.org/licenses/bsd-license.php
+
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include "InternalCryptLib.h"
+
+#include <openssl/objects.h>
+#include <openssl/x509.h>
+#include <openssl/pkcs7.h>
+
+
+/**
+ Verifies the validility of a PE/COFF Authenticode Signature as described in "Windows
+ Authenticode Portable Executable Signature Format".
+
+ If AuthData is NULL, then return FALSE.
+ If ImageHash is NULL, then return FALSE.
+
+ Caution: This function may receive untrusted input.
+ PE/COFF Authenticode is external input, so this function will do basic check for
+ Authenticode data structure.
+
+ @param[in] AuthData Pointer to the Authenticode Signature retrieved from signed
+ PE/COFF image to be verified.
+ @param[in] DataSize Size of the Authenticode Signature in bytes.
+ @param[in] TrustedCert Pointer to a trusted/root certificate encoded in DER, which
+ is used for certificate chain verification.
+ @param[in] CertSize Size of the trusted certificate in bytes.
+ @param[in] ImageHash Pointer to the original image file hash value. The procudure
+ for calculating the image hash value is described in Authenticode
+ specification.
+ @param[in] HashSize Size of Image hash value in bytes.
+
+ @retval TRUE The specified Authenticode Signature is valid.
+ @retval FALSE Invalid Authenticode Signature.
+
+**/
+BOOLEAN
+EFIAPI
+AuthenticodeVerify (
+ IN CONST UINT8 *AuthData,
+ IN UINTN DataSize,
+ IN CONST UINT8 *TrustedCert,
+ IN UINTN CertSize,
+ IN CONST UINT8 *ImageHash,
+ IN UINTN HashSize
+ )
+{
+ BOOLEAN Status;
+ PKCS7 *Pkcs7;
+ CONST UINT8 *OrigAuthData;
+ UINT8 *SpcIndirectDataContent;
+ UINT8 Asn1Byte;
+ UINTN ContentSize;
+
+ //
+ // Check input parameters.
+ //
+ if ((AuthData == NULL) || (TrustedCert == NULL) || (ImageHash == NULL)) {
+ return FALSE;
+ }
+
+ if ((DataSize > INT_MAX) || (CertSize > INT_MAX) || (HashSize > INT_MAX)) {
+ return FALSE;
+ }
+
+ Status = FALSE;
+ Pkcs7 = NULL;
+ OrigAuthData = AuthData;
+
+ //
+ // Retrieve & Parse PKCS#7 Data (DER encoding) from Authenticode Signature
+ //
+ Pkcs7 = d2i_PKCS7 (NULL, &AuthData, (int)DataSize);
+ if (Pkcs7 == NULL) {
+ goto _Exit;
+ }
+
+ //
+ // Check if it's PKCS#7 Signed Data (for Authenticode Scenario)
+ //
+ if (!PKCS7_type_is_signed (Pkcs7)) {
+ goto _Exit;
+ }
+
+ //
+ // NOTE: OpenSSL PKCS7 Decoder didn't work for Authenticode-format signed data due to
+ // some authenticode-specific structure. Use opaque ASN.1 string to retrieve
+ // PKCS#7 ContentInfo here.
+ //
+ SpcIndirectDataContent = (UINT8 *)(Pkcs7->d.sign->contents->d.other->value.asn1_string->data);
+
+ //
+ // Retrieve the SEQUENCE data size from ASN.1-encoded SpcIndirectDataContent.
+ //
+ Asn1Byte = *(SpcIndirectDataContent + 1);
+
+ if ((Asn1Byte & 0x80) == 0) {
+ //
+ // Short Form of Length Encoding
+ //
+ ContentSize = (UINTN) (Asn1Byte & 0x7F);
+ //
+ // Skip the SEQUENCE Tag;
+ //
+ SpcIndirectDataContent += 2;
+ } else if ((Asn1Byte & 0x82) == 0x82) {
+ //
+ // Long Form of Length Encoding, only support two bytes.
+ //
+ ContentSize = (UINTN) (*(SpcIndirectDataContent + 2));
+ ContentSize = (ContentSize << 8) + (UINTN)(*(SpcIndirectDataContent + 3));
+ //
+ // Skip the SEQUENCE Tag;
+ //
+ SpcIndirectDataContent += 4;
+ } else {
+ goto _Exit;
+ }
+
+ //
+ // Compare the original file hash value to the digest retrieve from SpcIndirectDataContent
+ // defined in Authenticode
+ // NOTE: Need to double-check HashLength here!
+ //
+ if (CompareMem (SpcIndirectDataContent + ContentSize - HashSize, ImageHash, HashSize) != 0) {
+ //
+ // Un-matched PE/COFF Hash Value
+ //
+ goto _Exit;
+ }
+
+ //
+ // Verifies the PKCS#7 Signed Data in PE/COFF Authenticode Signature
+ //
+ Status = (BOOLEAN) Pkcs7Verify (OrigAuthData, DataSize, TrustedCert, CertSize, SpcIndirectDataContent, ContentSize);
+
+_Exit:
+ //
+ // Release Resources
+ //
+ PKCS7_free (Pkcs7);
+
+ return Status;
+}
|